Our specific goal in Phase I of this effort is to demonstrate the use of a compact, portable, spectroscopic system for urinary stone analysis that will optimize the detection strategy and algorithms for the intraoperative identification and subsequent laser fragmentation of urinary calculi. We propose to make use of the near IR (NIR) excited Raman spectral characteristics of common calcifications associated with stone disease. This will enable differentiation between stones of distinct compositional type and also of stones from surrounding, non-target, soft tissues. Our preliminary spectroscopic data will be extended and used to develop a compact, portable, fiber-optic Raman spectrometer. This device will be used clinically, and eventually, intra-operatively during surgical percutaneous nephrolithotomies (PCNL). PROPOSED COMMERCIAL APPLICATION: Provide in-vivo laser Raman sensing of biochemical composition within a current laser lithotripsy.